Accumulator



FIG. 1 is a perspective view of an accumulator showing my new design;

FIG. 2 is a top view thereof;

FIG. 3 is a bottom view thereof;

FIG. 4 is a front view thereof;

FIG. 5 is a rear view thereof;

FIG. 6 is a right side view thereof; and,

FIG. 7 is a left side view thereof.

The broken lines shown in the drawing views represent unclaimed subject matter and form no part of the claimed design. 

The ornamental design for an accumulator, as shown and described. 